in reply to how to extract certain lines

here is what im try to type
example
HERE IS THE DATA
PLACED ABC;
DO NOT ENTER
PLACED BCD;
HERE IS THE DATA
PLACED ABC;
WHO ARE U
PLACED ABC;
I want to extract the lines started with "PLACED..
if the line "HERE IS THE DATA appear before it

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Re^2: how to extract certain lines
by neilh (Pilgrim) on Oct 26, 2004 at 04:29 UTC
    Try this

    while (<DATA>) {
    next unless /^HERE IS THE DATA/;
    my $line = <DATA>;
    print $line;
}



__DATA__
HERE IS THE DATA
PLACED ABC;
DO NOT ENTER
PLACED BCD;
HERE IS THE DATA
PLACED ABC;
WHO ARE U
PLACED ABC;

__OUTPUT__
PLACED ABC;
PLACED ABC;

    [download]

    Neil

[reply]
[d/l]
      Thank you Neil..
      I still have questions here.
      Why do you use my before $line
      what is the function of my here?
      Thank you
[reply]
        Hi dee00zee,
        The my puts the variable into scope within the while loop.
        For information have a look at perldoc perlintro and the discussion on lexical scope.

        Neil

[reply]
[d/l]
        my is used to declare and assign the variable $line. If you would 'use strict;' this is a requirement for the script to run.

        Manual for my: http://www.perl.com/doc/manual/html/pod/perlfunc/my.html

        Edit: Excuse me for this post, I somehow missed that the question was already answered.
[reply]

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